The invention relates to a device for depicting a linear optical marking in a room, comprising a housing with a light source that emits the light along an optical axis and a lens that both reflects the light and allows it to pass, that is arranged in front of the light source and through which the optical axis extends.
A corresponding device that utilizes a laser beam is disclosed in DE-A-102 17 108. In order to generate a line extending without interruption across a wide angle using the laser beam device, which is used in particular in the construction industry, it is provided that a laser beam bundle that penetrates a collimator lens shines on a rod lens, which comprises a semitransparent surface on the light source side in order to reflect a linear light beam in the direction of the light source. The non-reflected light then penetrates a completely transparent surface of the rod lens that is facing away from the light source, and is refracted in order to generate a linear light beam in a second direction that is opposite from the first direction.
In order to depict a line of visible light on a surface, starting directly in front of a housing that accommodates the light source, according to U.S. Pat. No. 6,502,319 several cylindrical lenses or mirrors are provided, by means of which the light beam emitted by the light source is distributed as needed.
Light beam leveling instruments pursuant to DE-U-203 04 117 and DE-U-203 04 114 comprise line lenses, which are composed of sections having different focal distances, in front of a light source via which a linear light beam is supposed to be created.
In order to generate two lines that intersect at a right angle on a work piece beneath an optical marking device according to DE-C-199 53 114 two lateral projection devices that are arranged next to each other are suggested, which each comprise a light source and an optical unit arranged in its optical path.
In order to generate an optical marking line spanning roughly 360° pursuant to U.S. Pat. No. 6,539,638 a partially transparent lens in the form of a cylinder is used.
From DE-C-36 04 500 we know of a terminal for a light conductor for dental applications. The light conductor is used to evenly illuminate a rectangular field. For this purpose a cylindrical lens is used, which comprises a trough-shaped recess.
Pursuant to US-A-2003/01 59 299 intersecting lines are depicted on a surface by means of lens arrangements.